Simultaneous and co-located wind measurements in the middle atmosphere by lidar and rocket-borne techniques

Abstract

Abstract. We present the first comparison of a new lidar technique to measure winds in the middle atmosphere, called DoRIS (Doppler Rayleigh Iodine Spectrometer), with a rocket-borne in situ method, which relies on measuring the horizontal drift of a target ("starute") by a tracking radar. The launches took place from the Andøya Space Center (ASC), very close to the ALOMAR observatory (Arctic Lidar Observatory for Middle Atmosphere Research) at 69 • N. DoRIS is part of a steerable twin lidar system installed at ALOMAR. The observations were made simultaneously and with a horizontal distance between the two lidar beams and the starute trajectories of typically 0-40 km only. DoRIS measured winds from 14 March 2015, 17:00 UTC, to 15 March 2015, 11:30 UTC. A total of eight starute flights were launched successfully from 14 March, 19:00 UTC, to 15 March, 00:19 UTC. In general there is excellent agreement between DoRIS and the in situ measurements, considering the combined range of uncertainties. This concerns not only the general height structures of zonal and meridional winds and their temporal developments, but also some wavy structures. Considering the comparison between all starute flights and all DoRIS observations in a time period of ±20 min around each individual starute flight, we arrive at mean differences of typically ±5-10 m s −1 for both wind components. Part of the remaining differences are most likely due to the detection of different wave fronts of gravity waves. There is no systematic difference between DoRIS and the in situ observations above 30 km. Below ∼ 30 km, winds from DoRIS are systematically too large by up to 10-20 m s −1 , which can be explained by the presence of aerosols. This is proven by deriving the backscatter ratios at two different wavelengths. These ratios are larger than unity, which is an indication of the presence of aerosols.

Winds and temperatures of the Arctic middle atmosphere during January measured by Doppler lidar

“…During the beginning of February, the maxima in temperature, zonal wind, and meridional wind intensified and descended further. These phenomena are closely connected to the preceding SSW: they are referred to as elevated stratopause and reformation of the polar vortex, which sometimes occur after stratospheric warmings (e.g., Labitzke, 1972;Manney et al, 2009). In contrast to this work, the two studies by Labitzke et al and Manney et al analyzed vortex split events with a complete breakdown of the polar vortex.…”

Spatial and temporal variability in MLT turbulence inferred from in situ and ground-based observations during the WADIS-1 sounding rocket campaign

“…A successful salvo of eight data sondes with other complementary launches allowed validation of wind measurements by the ALOMAR RMR lidar and is discussed in detail in Lübken et al (2016). …”

Validation of middle-atmospheric wind in observations and models

“…Validations of the method for nighttime observations have been presented by Hildebrand et al (2012) andLübken et al (2016). Measurements of temperatures and wind during day and night are presented in Baumgarten et al (2015).…”

“…Due to the novelty of these approaches and the absence of satellite data thorough validations with two independent measurement techniques synchronously assessing the same atmospheric volume are at a very early stage. Lübken et al (2016) presented comparisons between observations with the ALOMAR RMR lidar and eight nighttime starute soundings by rockets. In most cases good correspondence between both techniques has been found, even in the small-scale structures.…”

“…In the previous rocketlidar intercomparisons by Lübken et al (2016) only nighttime wind profiles have been investigated, daylight profiles will for the first time be validated in the study presented here.…”